Graves Top Velocity Stacks
Sale
$
426.55
$449.00
Save $22.45 (5% Off)
Graves Top Velocity Stacks, Graves Motorsports Yamaha R1 Top Velocity Stacks for the 2009 - 2014 models. This "Upper" or "Top" velocity stack is sold separately from the lower billet machined piece shown in picture. The upper stacks must be used with a YEC ECU or Flash Tune and correct setting will be supplied to customer upon purchase.
Developed by Graves for your Cross Plane Crank Yamaha R1.
This stack kit improves power throughout the entire RPM range.
The staggered tops allow the cylinders to share the available volume of air in the R1's air-box evenly at low and mid range RPMs.
The shorter-than-stock lower stacks (sold separately) feed the R1's appetite for big air when the upper stacks raise improving top end power.
These stacks were specifically developed on the Graves Yamaha Superbike give their riders the drivability needed to win races.
Notes: Both "Upper" and "Lower" R1 Velocity Stacks are designed to work together. The items are sold separately as you can use the performance-designed lowers with the stock uppers (uppers cannot be used with the stock lower stacks).